There are many circumstances where it is useful to quickly verify factual information, e.g., politics, media, stock market, retail scenarios, etc. However, users have access to substantial amounts of information from relatively non-authoritative sources such as blogs, forums, discussion groups, social networking sites, etc. Such sources may not be appropriate for verifying factual information. Even relatively authoritative sources such as Wikipedia® can include errors or controversial statements. In some cases, these errors or controversial statements are not annotated with citations to more authoritative sources, and are thus difficult to verify quickly.
One way for a user to verify a particular statement is to use a search engine, e.g., a web search engine such as Bing® or Google®. Web search engines generally receive user queries that include one or more search terms, and respond to the user queries with ranked search results based on the search terms provided in the user queries. For a user attempting to verify a statement, a general web search engine may make the user's task relatively difficult. For example, the user may need to browse through each of the search results to determine whether the individual results tend to support or contradict the statement. Moreover, relatively authoritative sources do not necessarily appear as high-ranked search results, which can make it even more difficult for the user to identify good supporting or contradicting evidence for the statement.